index parser: fix refcounting in case of errors, refactor
due to incorrect refcounting, on a bad revlog it was failing with:
*** glibc detected *** /usr/bin/python: corrupted double-linked list: 0x0816d318 ***
and a backtrace.
#!/bin/sh
echo "[extensions]" >> $HGRCPATH
echo "extdiff=" >> $HGRCPATH
hg init a
cd a
echo a > a
echo b > b
hg add
# should diff cloned directories
hg extdiff -o -r $opt
echo "[extdiff]" >> $HGRCPATH
echo "cmd.falabala=echo" >> $HGRCPATH
echo "opts.falabala=diffing" >> $HGRCPATH
hg falabala
hg help falabala
hg ci -d '0 0' -mtest1
echo b >> a
hg ci -d '1 0' -mtest2
# should diff cloned files directly
hg falabala -r 0:1
# test diff during merge
hg update 0
echo c >> c
hg add c
hg ci -m "new branch" -d '1 0'
hg update -C 1
hg merge tip
# should diff cloned file against wc file
hg falabala > out || echo "diff-like tools yield a non-zero exit code"
# cleanup the output since the wc is a tmp directory
sed 's:\(.* \).*\(\/test-extdiff\):\1[tmp]\2:' out